LAKEWOOD, Colo. (AP) _ A role-playing exercise designed to teach students about slavery has given the few chosen to be plantation owners a license to abuse and humiliate classmates, parents have complained.

But Lakewood High School officials said Wednesday they won't abandon the week-long activity although they have tightened supervision of the play- acting.

The Le Tigre Plantation was created by history teacher Bill Wright to augment the unit he and others teach on the Civil War.

About 300 students, mostly sophomores, are participating in the exercise, most as slaves or free blacks, but a few as plantation owners with unquestioned authority over their classmates.

After parents said some children were the victims of harsh treatment, school officials tightened supervision. But they said they're convinced the activity teaches a lesson.

''It teaches the evils of slavery, and the parents feel very comfortable with the activity in the classroom environment,'' said Principal Vince Greco. ''It shows what the slaves had to do. There's no physical punishment, it's just social status.

''Where the concern was was in the halls, the activities not monitored by the teachers, maybe overzealous students doing some hazing. And I agree with them. That was not the intent,'' he said.

Parents complained they'd heard of instances that made students late to class, had their homework destroyed, were forced to climb stairs until they were exhausted and were harassed verbally to the point of tears.

''They worst thing I've seen in the hall is a girl doing five jumping jacks,'' Wright said.

Students do have a list of rules, such as to be in their classrooms, standing by their desks when the bell rings and preface all questions or responses with ''Sir'' or ''Ma'am,'' but Wright said the students designated as slaves don't have to comply with demands they consider demeaning or inappropriate.